The plane, a CRJ-200 carrying 41 passengers from Chattanooga to Dallas-Forth Worth, made the emergency landing in Huntsville, Alabama, without incident.

Henson said passengers could smell the gas as they got off the plane, and that airline staff explained what went wrong.

"Whoever the person in charge in Chattanooga that did the fuel fill on that side of the plane, did not put the cap back on correctly or properly," Henson told WRCB.

Roger Nunamann, a pilot not involved in the flight, said the passengers were never in danger.

"It's not the first time it's happened and it wont be the last time it's happened," Nunamann told WAAY TV, the ABC station in Huntsville. "I've never known it to cause any kind of fire or catastrophic failure or crash."